[3.18] main/libwebp: patch CVE-2023-4863
Cherry-picked from !51544 (merged)
Patch from https://github.com/NixOS/nixpkgs/pull/254775 and matched against https://hg.mozilla.org/releases/mozilla-release/rev/e245ca2125a6eb1e2d08cc9e5824f15e1e67a566
Cherry-picked from !51544 (merged)
Patch from https://github.com/NixOS/nixpkgs/pull/254775 and matched against https://hg.mozilla.org/releases/mozilla-release/rev/e245ca2125a6eb1e2d08cc9e5824f15e1e67a566